This invention relates to sign-making apparatus which makes signs by using a sand-blast on a blank of degradable material and, more particularly, to such apparatus which is operable to degrade a synthetic blank in a fashion which gives the blank the appearance and texture of sand-blasted, or naturally weathered wood.
Sign-making apparatus using a sand-blast involves taking a substantially planar blank of substrate material which is degradable and applying a non-degradable stencil thereto. The sand-blast is directed at the stationary substrate and moved in both the vertical and horizontal directions to degrade the substrate surrounding the stencil. The stencil is then removed leaving raised areas forming the design and/or lettering of the stencil outline on the substrate such that it contrasts and is visually perceivable apart from the degraded portions of the substrate. This type of sign-making is described in the following U.S. Pat.:
U.S. Pat. No. 2,016,092 to Kavanaugh on Oct. 1, 1935; PA1 U.S. Pat. No. 2,109,000 to Waldo, Jr. on Feb. 22, 1938; PA1 U.S. Pat. No. 2,358,710 to Helgeson on Sep. 19, 1944; and PA1 U.S. Pat. No. 3,137,978 to Incantalupo on Jun. 23, 1964.
The Kavanaugh method relates to the formation of a non-degradable stencil from a latex rubber compound. An example of a substrate is wood to which the stencil is applied and sand-blasted resulting in grooves being formed in the wood parallel with the grain of the wood. The resultant grooves in the wood give the wood a weathered appearance which is a highly desirable effect.
The Waldo, Jr. method relates to treating a wood plank with shellac prior to the sand-blasting operation and also discusses the desirability of attaining a weather-beaten appearance due to the hard grains in the wood not being degraded to the same degree as the soft grains of wood.
The Helgeson invention and method relates to a method of preparing a rigid stencil and clamping the stencil against a substrate. There is no discussion as to types of substrate used or texture thereof as a result of the sand-blasting operation.
Lastly, the Incantalupo invention relates to a letter forming device used in sand-blasting on a stone medium.
The present invention concerns itself with the topography characteristics of the blank surface which has been subjected to the inventive sand-blast operation. In particular, it is generally desirable in the art to create parallel and alternating grooves and peaks in the sign surrounding the stencil, regardless of substrate material, which gives the sign a weathered appearance akin to wood which has either been naturally weathered, or subjected to a sand-blast, both of which act to augment the harder grains in the wood (which are formed during the slower, summer growth period of tree development) by degrading the softer grains thereof (which are formed during the quicker, spring growth period of tree development) located between the harder grains.